docs: def filter_out_spontaneous_genes(genes, custom_spont_id=None):
      """Return the DictList of genes that are not spontaneous in a model.
  
      Args:
          genes (DictList): Genes DictList
          custom_spont_id (str): Optional custom spontaneous ID if it does not match the regular expression ``[Ss](_|)0001``
  
      Returns:
          DictList: genes excluding ones that are spontaneous
  
      """
      new_genes = DictList()
      for gene in genes:
          if not is_spontaneous(gene, custom_id=custom_spont_id):
              new_genes.append(gene)
  
      return new_genes